Gas manufacture



Nov. 6, 1945.

E. E. STIMSON GAS MANUFACTURE Filed Jan. 1, 1943 FIG. I

' ess continuously by carrying out the comprise a furnace in which vortices are formed Patented Noy. 6, 1945 aAs' MANUFACTURE Edward Eric Stimson,

Spondon, near Derby, England, 'asslgnor to British Celanese Limited. London, England, a company of Great Britain v Application January 1, 1943, Serial No. 471.038

In Great Britain January 20, 1942 3 Claims. (c1. 48-203) This invention relates to improvements i'n gas manufacture and is especially concerned with the manufacture of mixtures of carbon monoxide and hydrogen. l

Industrial gas mixtures containing carbon monoxide and hydrogen, such as water-gas, are usually produced bypassing steam through a bed -'of coke previously heated to a high temperature by combustion and continuing the passage of steam until the drop in temperature caused by the endothermic water-gas reaction makes it necessary to replace the current of steam by a blast of air. It is, however, possible'to operate the proccausing the coke to react simultaneously with oxygen and steam sothat some of the coke is burnt to provide the heat for the water-gas reaction taking place simultaneously. The present invention is concemed'with such a continuous water-gas process in'which powdered coal, coke or other carbonaceous material is employed as starting material.

According to the invention, a vortical suspension of powdered carbonaceous material in steamis caused to react by heat from an adjacent vortex of powdered carbonaceous material burning in oxygen. In this. way it has been found possible to convert carbonaceous material, such as coal, coke, and the like, into water-gas very rapidly and with a high emciency.

In its simplest form the apparatus used for process of the invention may from the powdered carbonaceous material and steam and from the powdered carbonaceous materlal and oxygen, the vortices preferably being arranged alternately and one above the other and with the same direction of rotation. Such vortices may be produced by injecting the solid carbonaceous material together with the oxygen or steam tangentially and in a horizontal or substantially horizontal direction into a furnace of circular cross-section. It is most convenient to withdraw the gases produced at or near the bottom of the furnace so that the vortices together form a helix, 1. e. the burning and reacting carbonaceous particles and the gases formed or introduced follow a helical path from top to bottom of the furnace.

In practice, however, it is preferred to form more than one such helix by forming a plurality of vortices in the same plane. Thus, uy providing four points of introduction in the furnace in a common plane it ispossible to generate four vor-.

tices in this plane. At a lower level there may I be arranged verticaly below the points of intro- I duction referred to, four additional points of introduction, so that under each vortex a further vortex is formed. Preferably, the arrangement is such that thevortices alternate in the vertical plane so that each carbonaceous material-steam vortex is adjacent one or two carbonaceous material-oxygen vortices. The vortices in each plane may be of the same type or may differ, and in the latter case they preferably alternate so that uniform heating is obtained. It will be appreciated that the use of four vortices is referred to only as an example and any number may be formed, as desired. These vortices can be pro duced very easily in practice by directing the jets supplied with carbonaceous material and steam or oxygen into the furnace along a path not coinciding with a radius. "In this way, the Jets introduced react upon each other and form a D raiity of vortices.

Where a number of vortices are formed in 'a common plane, and even where a single vortex is formed and hence a single helical path is generated by the falling carbonaceous material, a more or less well-defined column unoccupied by the carbonaceous solid is formed near thecentre of the furnace. Thus, the central portion of the furnace may be occupied by a pillar without substantially reducing the effective capacity of the furnace and by constructing this pillar of firebrick or other suitable material the furnace may be given an increased heat capacity. Such a column may be employed for withdrawing the gases from the bottom of the furnace or by piercing the column for withdrawing the gases from other points at any desired height within thefurnace. Where a plurality of co-planar vortices is formed in the furnace such a column may be of such shape as to present a concave face to each vortex the formation and maintenance whereof is thus facilitated.-

The reaction between the solid carbonaceous material and steam is one which needs for efficiency a fairly high reaction temperature. Nevertheless, by operating in the manner described, it is possible to use reaction temperatures somewhat below those normally employed and comsiderably below the temperature to which it is 'usualto raise the bed of carbonaceous material used in the intermittent process during the blow" period. In general, it is-not necessary in the process of the invention to exceed temperatures of 1,000 0., temperatures of 800-1,000 being quite eflective, although higher temperatures,

e. 5. up to 1,500 or 1,800 C. may be used if desired.

The gases leaving the furnace may carry with air or oxygen being used in the process them unburnt residues frornthe carbonaceous material and are therefore best passed first through a settling chamber and thereupon may be used immediately or cooled, for instance, by use in waste heat boilers before being passed to further treatment, for instance desulphurisation. or removal of carbon dioxide.

Most of the unburnt residue from the powderedcarbonaceous material consists of inorganic matter' which will settle as a fine powder upon the floor of the furnace and can be removed from time to time or continuously by means of a mechanical stoker, rotating hearth or like device.

It will be appreciated that while the heat a needed in the process has been stated to be produced by powdered carbonaceous material burning in oxygen, air or air enriched in oxygen can also be used for this purpose although the watergas then produced will contain nitrogen. amount of oxygen needed can be reduced by preheating the steam used in the process; such preheating may be to a moderate temperature, e. g. 500 C., or to the reaction temperature. maintained within the furnace or even to a higher temperature.

- vided with supply and return pipes 6 and '1 respectively. The bottom of the furnace is closed by furnace door 8. Arranged in the centre of the furnace is a tube 9 of heat resisting steel provided with a refractory jacket l0. Inlets' II, I!

are provided round the furnace at several levels.

In operation steam and powdered fuel are introduced through the inlet I land air or oxygen and powdered fuel through the inlets l2 so as to produce the vortices indicated in broken lines in Figure 2. There are thus formed vortices of both steam-powdered fuel and airor oxygen-powdered fuel in each layer, the vortices in adjacent layers alternating in type from top to bottom of the v furnace.

Spent carbonaceous material mus to the bottom 7 of the furnace cooled by the circulation of waterthrough the jacket 5, the water being suppli d at inlet 6 and withdrawn from outlet 1, and can be withdrawn from time to time through the furnace door 8. Gaseousproducts are withdrawn through the pipe 8 and may be used before being passed to storage for preheating steam and/or after having been freedfrom suspended particles, for example by means of a cyclone separator.

aseasss Having now described my invention what I desire to secure by Letters Patent is:

1. Method of producing industrial containing carbon monoxide and hydrogen, which comprises injecting a carbonaceous material and steam into a substantially circular reaction chamberin a. direction not coinciding with a radius of said chamber so as to form a vortex and injecting carbonaceous material and, oxygen chamber in the same plane into said chamber in the same plane and in opposed to the direction of injection of the carbonaceous material and steam to form a second' vortex, the oxidation of the carbonaceous material, in the second vortex supplying heat to the reactants.

2. Method of producing industrial gas mixtures containing carbon monoxide and hydrogen, which comprises injecting a carbonaceous material and steam into a substantially circular reaction chamber in a direction not coinciding with a radius of said chamber to form a vortex and injecting carbonaceous material and oxygen and in a direction opposed to the direction ,of injection of the carbonaceous material and steam to form a second vortex, the oxidation of the carbonaceous material in the second vortex supplying heat to the reactants, said injections being effected at a plurality of vertically spaced pointsto form a plurality of superimposed vortices having a common axi and the same direction of rotation, and in such a manner that a vortex comprising carbonaceous material. and steam alternates along the common axis with a vortex comprising carbonaceous material and oxygen.

3. Method of producing industrial gas mixtures containing carbon monoxide and hydrogen, which comprises injecting carbonaceous material and steam into a substantially circular reaction cham- 40 ber at a plurality of circumferentially and vertiof the carbonaceous 'jections forming carbonaceous material and steam and vortices of cally spaced points and in'directions not coinciding with a radius of said chamber to form a series of vortices, and injecting carbonaceous material and oxygen therein at a plurality of circumferentially and vertically spaced points andv in directions opposed to the direction of injection material and steam toform a second series of vortices, the oxidation of the carbonaceous material in the second series of .vortic'es supplying heat to the reactants, said inin the same plane vortices of carbonaceous material and oxygen and a plurality of superimposed vortioes having a common axis and the same direction of rotation, a vortex comprising carbonaceous material and steam alternating along the common axis with a 'vortex'comprising carbonaceous material and oxygen.

' EDWARD ERIC s'mrson.

gas mixtures a direction into said 

